55784447813 has 2 divisors, whose sum is σ = 55784447814. Its totient is φ = 55784447812.

The previous prime is 55784447809. The next prime is 55784447869. The reversal of 55784447813 is 31874448755.

It is an a-pointer prime, because the next prime (55784447869) can be obtained adding 55784447813 to its sum of digits (56).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35833732804 + 19950715009 = 189298^2 + 141247^2 .

It is a cyclic number.

It is not a de Polignac number, because 55784447813 - 2² = 55784447809 is a prime.

It is a super-2 number, since 2×55784447813² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55784447413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27892223906 + 27892223907.

It is an arithmetic number, because the mean of its divisors is an integer number (27892223907).

Almost surely, 2^55784447813 is an apocalyptic number.

It is an amenable number.

55784447813 is a deficient number, since it is larger than the sum of its proper divisors (1).

55784447813 is an equidigital number, since it uses as much as digits as its factorization.

55784447813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15052800, while the sum is 56.

The spelling of 55784447813 in words is "fifty-five billion, seven hundred eighty-four million, four hundred forty-seven thousand, eight hundred thirteen".